Graft copolymer and method for preparing the same

Abstract

The present invention relates to a graft copolymer and a method for preparing the same, and more precisely a graft copolymer prepared by the steps of preparing a living activator with a single monomer and a block copolymer of a vinyl aromatic hydrocarbon or a conjugated diene hydrocarbon; and then grafting the prepared living activator to polyolefin polymer, and a method for preparing the same. According to the method of the present invention, the individual vinyl aromatic hydrocarbon or conjugated diene hydrocarbon polymers, and a block copolymer thereof, can be grafted onto chlorinated polyolefin polymer as a branch by using a living activator, and the resultant graft copolymer can be widely applied to various high molecular additives, compatabilizers, waterproof sheets and asphalt, etc.

1 . A graft copolymer represented by the following formula 1: 
         A graft B 1 -block-B 2     [Formula 1] Wherein, A is chlorinated polyolefin with a degree of chlorination of 1˜99%, and each of B 1  and B 2  are independently polymers composed of a vinyl aromatic hydrocarbon or a conjugated diene hydrocarbon.    
   
   
       2 . The graft copolymer according to  claim 1 , wherein the number average molecular weight of the chlorinated polyolefin is 1,000˜1,000,000.  
   
   
       3 . The graft copolymer according to  claim 1 , wherein the number average molecular weight of the B 1 -block-B 2  block copolymer is 1,000˜1,000,000.  
   
   
       4 . The graft copolymer according to  claim 1 , wherein the graft rate of the B 1 -block-B 2  block copolymer is 0.1˜99%.  
   
   
       5 . The graft copolymer according to  claim 1 , wherein if B 1  and B 2  in the B 1 -block-B 2  block copolymer are different polymers, the weight ratio of B 1  and B 2  is in the range of 0˜100 weight %.  
   
   
       6 . The graft copolymer according to  claim 1 , wherein the vinyl aromatic hydrocarbon is one or more compounds selected from a group consisting of styrene, α-methylstyrene, 3-methylstyrene, 4-methylstyrene, 4-propylstyrene, 1-vinylnaphthalene, 4-cyclohexylstyrene, 4-(p-methylphenyl)styrene, and 1-vinyl-5-hexylnaphthalene.  
   
   
       7 . The graft copolymer according to  claim 1 , wherein the conjugated diene monomer is one or more compounds selected from a group consisting of 1,3-butadiene, 2,3-dimethyl-1,3-butadiene, piperylene, 3-butyl-1,3-octadiene, isoprene and 2-phenyl-1,3-butadiene.  
   
   
       8 . A method for preparing the graft copolymer of  claim 1 , which comprises the following steps: 
 a) preparing a living activator for a single or a block copolymer selected from a vinyl aromatic hydrocarbon and a conjugated diene hydrocarbon in the presence of a hydrocarbon solvent and an organic lithium compound, and    b) preparing the graft copolymer by reacting the living activator with chlorinated polyolefin.    
   
   
       9 . The method for preparing the graft copolymer according to  claim 8 , wherein the hydrocarbon solvent is one or more compounds selected from a group consisting of n-pentane, n-hexane, n-heptane, isooctane, cyclohexane, toluene, benzene and xylene.  
   
   
       10 . The method for preparing the graft copolymer according to  claim 8 , wherein the organic lithium compound is one or more compounds selected from a group consisting of methyl lithium, ethyl lithium, isopropyl lithium, n-butyl lithium, sec-butyl lithium, tert-butyl lithium, n-decyl lithium, tert-octyl lithium, phenyl lithium, 1-naphthyl lithium, n-eicosyl lithium, 4-butylphenyl lithium, 4-tolyl lithium, cyclohexyl lithium, 3,5-di-n-heptylcyclohexyl lithium and 4-cyclopentyl lithium.  
   
   
       11 . The method for preparing the graft copolymer according to  claim 8 , wherein the reaction to prepare a living activator is not terminated until at least 99% of the monomer is consumed.  
   
   
       12 . The method for preparing the graft copolymer according to  claim 8 , wherein a polar solvent is additionally added in step b).  
   
   
       13 . The method for preparing the graft copolymer according to  claim 12 , wherein the polar solvent is one or more compounds selected from a group consisting of tetrahydrofuran, ethyl ether and tetramethylethylenediamine.  
   
   
       14 . The method for preparing the graft copolymer according to  claim 12 , wherein the polar solvent is used less than 30 weight part for the weight of the hydrocarbon solvent.  
   
   
       15 . The method for preparing the graft copolymer according to  claim 8 , wherein a reaction accelerator is additionally added in step b).  
   
   
       16 . The method for preparing the graft copolymer according to  claim 15 , wherein the reaction accelerator is one or more compounds selected from a group consisting of tert-aliphatic amine, tert-diamine, triamine, dipyrrolidoneethane and tetramethyl-ethylene-diamine (TMEDA).  
   
   
       17 . The method for preparing the graft copolymer according to  claim 15 , wherein the content of the reaction accelerator is 0.5˜30 molar rate for the living activator.